Blade tension means for hair clipper blades



March 29, 1966 E. w. Tssmsms iifizfiw BLADE TENSION MEANS FOR HAIR CLIPPER BLADES Filed June 21, 1965 INVENTOR. EDUARD W. T! ETJQJS United States Patent 3,242,570 BLADE TENSION MEANS FOR HAIR CLIPPER BLADES Eduard Willem Tietjens, Drachten, Netherlands, assignor to North American Philips Company, Inc., New York, N.Y., a corporation of Delaware Filed June 21, 1963, Ser. No. 289,502 Claims priority, application Netherlands, July 4, 1962, 280,545 6 Claims. (Cl. 30221) The invention relates to a hair clipping apparatus, particularly a hair clipping attachment to be combined with a dry shaver. The hair clipper attachment includes a stationary cutting member and a reciprocating driven cutting member which is pressed fiat to the first-mentioned cutting member by a spring, the latter exerting its pressure upon the part of the reciprocating cutting member adjoining the teeth.

It is known to support a spring in a housing in a manner such that the entire spring is disposed at the side of the reciprocating cutting member. Thus, a helical spring or a leaf or wire spring may be used. The disposition and the manner in which pressure is exerted on the attachment are satisfactory, and, additionally, means for adjusting the spring pressure can readily be added.

However, this arrangement has a limitation in especially the so-called hair-clipping attachment for dry-shaving apparatus the construction of which must be fiat and simple, the space required for the said known spring arrangements is not readily available, While the possibility of removing the attachment comprising the cutting members and the spring as a unit from the dry-shaving apparatus is generally desired.

It is an object of the present invention to provide a simple solution to the aforesaid problem by providing a hair-clipping apparatus constructed in accordance with the invention which is characterized in that at that side of the set of cutting members which is remote from the reciprocating cutting member the spring is supported at a point which with respect to the driving point is situated opposite the teeth of the cutting members and from this point extends in the longitudinal direction to the point at which it exerts its pressure at the other end, thus crossing the plane dividing the cutting members.

Hence a spring is employed which substantially extends in one direction and can readily be so shaped according to the particular circumstances that it occupies a small amount of height and which extends from its end dis posed between the point at which the reciprocating cutting member is driven and the teeth of the cutting members, which end hereinafter will be referred to as the thrust end, to the rear to its end disposed on the other side of the driving point, which end hereinafter will be referred to as the securing end.

In this manner the height required by the thickness of the cutting members is used to accommodate the spring so that the entire assembly can be maintained flat and in addition a spring of such length can be accommodated that its legs can, if desired, readily follow the reciprocating movement of the driven cutting member, so that there is no friction between this cutting member and the thrust end of the spring while, at the same time, retaining a favorable thrust point.

In a hair clipping apparatus built in a dry-shaving apparatus it is known to bias the cutting members towards one another by means of a spring in the form of a hairpin which is moved from the rear over the cutting members so that these members are embraced by the limbs of the spring. To avoid a long path for slipping the spring on and to ensure that the spring remains in position, however, comparatively short limbs are used so that a favor- 3,242,570 Patented Mar. 29, 1966 able disposition of the thrust end with respect to the securing end is by no means obtained, unlike the arrangement according to the present invention, in which a small spring pressure is sufiicient due to the fact that the force is exerted comparatively near to the cutting teeth, while the fact that the spring extends substantially in one direction provides a satisfactory securement.

Another object of the invention is to provide at its securing end a spring which is partly accommodated in a recess in that wall of the casing on which the non-driven cutting member rests, While this member is provided on both sides with cut-away portions through which spring legs are passed, the thrust ends of which engage the outer surface of the driven cutting member adjacent the cutaway portions. This arrangement provides simplicity of mounting, the securing end being disposed on one side of the plane dividing the cutting members and the thrust ends on the other side. In addition, the spring is lighter and an even pressure on the driven cutting member over a large width is produced by the fact that two spring legs perform the same function.

The arrangement is preferably further characterized in that a frame-shaped spring is used, the two sides of the spring passing through the cut-away portions being joined above the driven cutting member so as to form a U-shaped part which constitutes the thrust end.

As a result the function of exerting even pressure can be assigned to a single spring, but in addition a possibility is produced which is utilized in a favorable embodiment which is characterized in that the lateral cutaway portions and the spring are so long that the set of cutting members is enabled to slide under the spring from a rest position to an operative position, in which latter position the spring pressure is exerted at an area nearer the cutting teeth than in the rest position.

As a result the spring is given an additional function which consists in that, while in the operative position the desired pressure is exerted, in the rest position the reciprocating cutting member is substantially released so that it can readily be removed.

In order that the invention may readily be carried into effect an embodiment thereof will now be described, by way of example, with reference to the accompanying diagrammatic drawings so that several details will emerge which can advantageously be used.

The figures show only the set of cutting members and the associated spring construction, because such a set can be attached in known manner, which need not be specified, to a wall of the housing, which may be fiat, of a hair clipping attachment to be combined with a dry-shaving apparatus.

FIG. 1 is an exploded view of a first embodiment.

FIG. 2 is a side elevation View of the set shown in FIG. 1 in which the component parts are mounted in position.

FIG. 3 is a perspective view of a second embodiment in the operative position.

FIG. 4 is a perspective view of this embodiment in the rest position.

The blade set shown in FIG. 1 comprises a fixed hair clipping member 1 and a driven hair clipping member 2. When the hair clipping attachment is mounted, for example, on a dry-shaving apparatus, a driving shaft thereof, which performs a reciprocating movement, engages in an aperture 3 in the member 2. The surface which is shown as the upper surface in the figure is to be mounted on the shaving apparatus. The fixed mem ber 1 is secured to the wall of the housing of the hair clipping attachment remote from the housing of the dryshaving apparatus, and in known attachments this wall forms the bottom of a flat, dished-out housing, the edges of which engage corresponding edges of the housing of the dry-shaving apparatus. The dished-out housing at its other side above the cutting member 2, may either be open or be closed by a cover, through which the driving shaft is passed through the aperture 3. The pivotal point for the reciprocating movement of the cutting member 2 is constituted by a pin 4 which is passed through an aperture 5 in the cutting member 2. The pin 4 is integral with a projection 6 and functions to space the rear parts of the cutting members 1 and 2; this projection together with the pin 4 may be secured to the member 1 but may alternatively be integral with the bottom of the housing of the hair-clipping apparatus and project through an aperture in the member 1 so as to contribute to the attachment of the member 1.

FIG. 2 illustrates that the cutting member is pressed fiat into engagement with the fixed member 1 by a spring 7, the pressure being exerted at a point or notch 8 of the part of the reciprocating member 2 adjacent teeth 9.

With regard to the disposition relative to the entire assembly of the cutting members, FIG. 2 shows that at the side of this assembly remote from the reciprocating member 2 the spring is supported at an area which with respect to a vertical transverse plane passing through the center of the blade set lies opposite the teeth 9 and 10, more particularly in parts 11 and 12 of the fixed member 1. From this area the spring 7 extends longitudinally to the thrust point 8 at the other end so as to cross the plane dividing the cutting members. The leg of the spring crossing the reciprocating member 2 passes through a cut-away portion 13 and then engages the outer surface of this member.

It will be evident that at the securing end which projects below the fixed member 1 the part 14 of the spring 7 must be accommodated in the recess in the underlying wall of the housing (not shown) by which the fixed member 1 is supported. FIG. I particularly shows that this member 1 also has a cut-away portion 15 at the area at which it is crossed by the spring 7 while the thrust end 16 of the spring engages the outer surface of driven member 2 adjacent to this cut-away portion.

FIG. 1 shows that on the other side of the blade set a similar spring 16 is used and that at this side the members have corresponding cut-away portions, which need not be separately described after the description of the disposition of the spring 7. It will be appreciated that a disposition of a spring on each side of the set of cutting members provides an even pressure on the reciprocating member throughout the width of the row of teeth 9.

It also should be noted that the spring 7 (and correspondingly the spring 16) is secured due to the fact that its securing end 17, which is bent upwards into the shape of a hook, and is held in the interstice between the cutting members and engages the fixed member 1 at the point 11 and from there extends below a stud 18 projecting into the cut-away portion 15. The thrust end 16 of the spring 7 engages the driven member 2 at the point 8. At the point 11 the edge of the cut-away portion 15 has a small notch by which the spring 7 is held in position.

In the embodiment shown in FIGS. 3 and 4 the bottom of the housing of the hair-clipping attachment is represented schematically by a plate 19. In this embodiment the arrangement of the spring and its function as desrcibed with reference to the embodiment shown in FIGS. 1 and 2 are recognizable for the greater part, however, the spring 20 now has the form of a frame, two sides 22 and 23 of which pass through the cut-away portions, for example, at 21, and are joined above the driven member 24 to form a U-shaped part 22, 23, 25 which forms the thrust end on the driven member 24. A recess 26 is formed in the plate 19 of the housing and in which the bent securing end 27 of the spring 20 is accommodated. In this embodiment recess 26 is in the form of a groove into which the spring is pressed or trapped by the fixed cutting member 28 which by means (not shown) 4 is slidably secured to the plate 19. In FIG. 3 the shaft (not shown) for driving the member 24 projects into a narrow end 29 of a aperture 30.

When the set of cutting members 24, 28 is moved from the position shown in FIG. 3 to the position shown in FIG. 4 the said shaft is brought into the wider part of the aperture 30 so that the member 24 is no longer driven, although the shaft may continue reciprocating. Since in this position the spring 20 has a large span with respect to the point at which the member 24 is supported by a pin 30a, the spring pressure is decreased so that the member 24 is readily removable. Obviously, the means for securing the member 28 to the plate 19 of the housing are such as to permit the said sliding movement.

While I have shown and described the preferred em bodiment of my invention, it will be understood that the latter may be embodied otherwise than as herein specifically illustrated or described and that in the illustrated embodiment certain changes in the details of construction and in the arrangement of parts may be made without departing from the underlying idea or principle of the invention within the scope of the appended claims.

What I claim:

1. A hair clipping device for a combination dry shaver and hair clipper comprising a fixed, toothed, cutting member, a reciprocably-driven toothed cutting member, a plate adjacent to said fixed cutting member and provided with a groove therein, a spring mounted so as to exert pressure on said driven cutting member whereby said driven cutting member is urged into flat engagement with said fixed member, said fixed member being provided with cut-away portions in the sides thereof, one end of said spring being held in the groove of said plate adjacent to said fixed cutting member, the intermediate portion of said spring being passed through said cut-away portions in said fixed cutting member, the thrust end of said spring engaging the outer surface of said driven cutting member adjacent to said cut-away portions to thereby form a unitary structure of said plate, fixed cutting member and driven cutting member.

2. A hair clipping device for a combination dry shaver and hair clipper as claimed in claim 1 wherein said spring is U-shaped and legs thereof pass through said cut-away portions and the bight part of said spring engaging the outer surface of said driven cutting member to form the thrust end of said spring.

3. A hair clipping device for a combination dry shaver and hair clipper as claimed in claim 2 wherein said. cutaway portions and said spring have such a length and configuration that both of said cutting members may be moved simultaneously from an inoperative to an operative position wherein in the latter position the spring pressure is exerted at an area more remote from the cutting teeth than in the inoperative position.

4. A hair clipping device for a combination dry shaver and hair clipper as claimed in claim 2 wherein said free ends of the spring are held in the groove in said plate by parts of said fixed cutting member.

5. A hair clipper device for a combination dry shaver and hair clipper comprising a movable assembly including a fixed, toothed cutting member and a reciprocally driven toothed cutting member, a plate adjacent to said fixed cutting member, a spring mounted in said hair clipper for exerting pressure on said driven cutting member whereby said driven cutting member is urged into flat engagement with said fixed member yet said movable assembly may be slid in a plane parallel to the plane of said plate, and means on said plate for holding an end of said spring thereon, the thrust part of said spring engaging the outer surface of said driven cutting member adjacent to the teeth thereof.

6. A hair clipper device for a combination dry shaver and hair clipper comprising a movable assembly including a fixed, toothed cutting member and a reciprocally driven toothed cutting member, a plate adjacent to said fixed cutting member, a spring mounted in said hair clipper for exerting pressure on said driven cutting member whereby said driven cutting member is urged into flat engagement with said fixed member yet said movable assembly may be slid in a plane parallel to the plane of said plate, a groove in said plate extending parallel to the longitudinal axis of said plate, and a part of said spring being in said groove, said fixed cutting member having a portion overlying said part of the spring in said groove and maintaining the same therein by said fixed cutting member.

References Cited by the Examiner UNITED STATES PATENTS WILLIAM FELDMAN, Primary Examiner.

MILTON S. MEHR, Examiner.

J. C. PETERS, Assistant Examiners. 

5. A HAIR CLIPPER DEVICE FOR A COMBINATION DRY SHAVER AND HAIR CLIPPER COMPRISING A MOVABLE ASSEMBLY INCLUDING A FIXED, TOOTHED CUTTING MEMBER AND A RECIPROCALLY DRIVEN TOOTHED CUTTING MEMBER, A PLATE ADJACENT TO SAID FIXED CUTTING MEMBER, A SPRING MOUNTED IN SAID HAIR CLIPPER FOR EXERTING PRESSURE ON SAID DRIVEN CUTTING MEMBER WHEREBY SAID DRIVEN CUTTING MEMBER IS URGED INTO FLAT ENGAGEMENT WITH SAID FIXED MEMBER YET SAID MOVABLE ASSEMBLY MAY BE SLID IN A PLANE PARALLEL TO THE PLANE OF SAID PLATE, AND MEANS ON SAID PLATE FOR HOLDING AN END OF SAID SPRING THEREON, THE THRUST PART OF SAID SPRING ENGAGING THE OUTER SURFACE OF SA ID DRIVEN CUTTING MEMBER ADJACENT TO THE TEETH THEREOF. 